Exemplo_phar

Date.php

<?php
//colocar na pasta app
namespace MyApp;
class Date {
    public static function next_week()
    {
        $datetime = new \DateTime(); 
        $datetime->add(new \DateInterval('P7D'));
        return $datetime->format('Y-m-d');
    }
}

index.php

<?php 
include_once 'phar://Myapp.phar';
echo 'PHP Arquive: ' . MyApp\Date::next_week()  . "\n";

phar-complile.php

<?php
//Cria o arquivo phar
$phar = new Phar('Myapp.phar');
//adiciona pastas ao "include_path"
$phar->buildFromDirectory(dirname(__FILE__) . '/app','/\.php$/');

//compacta
$phar->compressFiles( Phar::GZ);
$phar->stopBuffering();

//paremetro raiz
$phar->setStub($phar->createDefaultStub('Dates.php'));